Evie Gane has signed a new Pompey contract, subject to FA approval.
The defender has penned a one-year contract, with a club option of an additonal 12 months.
The 23-year-old rejoined the Blues back in January after she left for Coventry last August.
She initially arrived on the south coast in July 2021 following her departure from London Bees.
Gane has made 45 appearances across her two spells at the club, scoring two goals.
Blues boss Jay Sadler said: "I’m extremely happy that she has committed her future to Pompey.
"Evie has established herself here over two stints and has become a very important member of our squad.
"She brings calmness on the pitch and she really embodies the team values.
"Last season was about about gaining confidence and being patient with her, since rejoining. I can now see a real determination to help this club and to be successful here."
Gane added: "I’m super excited to be a part of this new era at Portsmouth.
"The club has helped me so much on and off the pitch and I wouldn’t want to be anywhere else.
"Since being back I’ve found my love for football again and I can’t wait to help push the club on in the new season."